CN104401003A - 3D printing-based reflective polarizing film preparation method and device thereof - Google Patents

Abstract

The invention relates to a method for preparing a reflective polarizing film based on 3D printing, comprising the following steps: 1. Establishing a three-dimensional digital model of the reflective polarizing film, and converting it into a work instruction for controlling the work of a 3D printing device, including printing the reflective polarizing film 2. Put the first raw material and the second raw material into the feed chamber of the 3D printing device respectively, and convert 3. The 3D printing equipment alternately executes the first instruction and the second instruction, and the printing head alternately sprays the liquid first raw material and the second raw material into the forming area, and makes the sprayed raw material solidify quickly, spraying a layer of solidified one layer Layers are stacked layer by layer to form a reflective polarizing film in which the first refractive index film and the second refractive index film are alternately laminated with hundreds of layers of film. The method and device can simplify the preparation process of the reflective polarizing film and improve the work production efficiency.

Description

A method and device for preparing a reflective polarizing film based on 3D printing

technical field

The invention relates to the technical field of preparation of reflective polarizing films, in particular to a method and device for preparing reflective polarizing films based on 3D printing.

Background technique

At present, Brightness Enhancement Film (BEF) is widely used in light-emitting modules to gather the light emitted by the light source, especially on display devices such as monitors. Brightness Enhancement Films are often used to increase display brightness and reduce display energy consumption. .

BEF is divided into prism-shaped BEF and reflective polarizing film.

Please refer to FIG. 1 , which is a schematic diagram of a known prism-shaped BEF used in a backlight module of a liquid crystal display. As shown in the figure, the prism-shaped BEF structure 1a includes: a main body portion 10a and a plurality of prism structures 11a. The plurality of prism structures 11a are all in the shape of triangular prisms, and are regularly arranged on the main body 10a. Through the brightness-enhancing film structure 1a, the divergent light with a large viewing angle is gathered and emitted in a smaller angle range, thereby achieving the light-gathering effect. However, in the conventional brightness enhancement film structure, the heights of individual prism units constituting the light-condensing prism structure layer are the same. When light penetrates and exits the prism structure layer, negative optical effects such as Newton's rings and Moiré ripples are likely to occur; at a larger light emitting angle, other luminous light cannot be effectively concentrated, resulting in light leakage. Aiming at the prism structure part of the brightness enhancement film, a variety of related technologies have been developed to improve the luminous efficiency.

For example, in the patent CN201220158721.1, a brightness enhancement film with a prism structure is disclosed, wherein every five prism columns is a cycle, and the height of the first prism column from the left end is 17um, and the height of the second prism column is 12.5um. um, the heights of the following three prism columns are all 15um; another example is patent CN201120246068.X, which discloses a brightness enhancement film structure, in which the prism parts are in a staggered dislocation structure. By changing the prism structure, the Newton ring phenomenon can be alleviated, and the uniformity of the light field distribution of the brightness enhancement film can be improved to achieve the effect of covering or hiding defects.

Please refer to FIG. 2 , which is a schematic diagram of a conventional brightness enhancing film manufacturing device. The manufacturing device 1b includes a feeding device 10b and a set of discharging rollers 12b. The feeding device 10b and the set of discharging rollers 12b deliver a polyester film 11b to the feeding roller 22b. The feed roller 22b coats the UV-curable glue 21b onto the surface of the 11b film. The mold roller 23b rolls out a prism microstructure 24b on the surface of the UV curable glue 21b. However, the base film 11b is unwound and entered by the feeding device 10b. Because the tension is too large, it is easy to cause excessive stretching on both sides of the base film 11b to form swaying; the polyester film 22b is completed by a coating process, and the coating process is likely to cause excessive Tension and local relaxation lead to defects such as uneven coating; due to the very high requirements on the surface accuracy and surface finish of the brightness enhancement film, the production of the mold 23b is a major technical problem today. In a word, the preparation method has complicated process procedures and low production efficiency, which is unfavorable for simplifying production.

Please refer to FIG. 3 , which is a schematic structural diagram of a known reflective polarizing film applied to a backlight module. The reflective polarizing film structure 1c includes two materials 10c and 11c with different refractive indices, and the two layers of materials with different refractive indices are overlapped multiple times, such as hundreds of times or more. The production process of the film is as follows: firstly, two kinds of polymer films are alternately extruded into hundreds of layers, and the thickness is only 200um; The refractive index of a film changes in the stretching direction, thereby forming a thin film material whose refractive index alternately changes in this direction and whose refractive index in the vertical direction is basically constant. In order to make the range of action cover the visible light band, according to the formula:

nh = (2 m +1) λ /4 (m = 0,1,2,…) (1)

Where n is the refractive index of the film, and λ is the wavelength of the incident light. The thickness of the polymer film layer changes gradually along with its thickness direction. The manufacturing process is very complicated, and stretching technology and film thickness control are major technical problems.

Contents of the invention

The purpose of the present invention is to provide a method and device for preparing a reflective polarizing film based on 3D printing, simplify the preparation process of the reflective polarizing film, and improve work and production efficiency.

In order to achieve the above object, the technical solution of the present invention is: a method for preparing a reflective polarizing film based on 3D printing, comprising the following steps:

Step S1, establish a three-dimensional digital model of the reflective polarizing film, and convert it into a work instruction for controlling the work of the 3D printing device, including the first instruction for printing the first refractive index film of the reflective polarizing film and the second instruction for printing the reflective polarizing film. Second Directive for Refractive Index Films;

Step S2, putting the first raw material for printing the first refractive index film and the second raw material for printing the second refractive index film into the feeding chamber of the 3D printing device respectively, and converting the first raw material and the second raw material into a liquid state;

Step S3, the 3D printing device alternately executes the first instruction and the second instruction, and the printing head alternately sprays the liquid first raw material and the second raw material into the forming area, and makes the sprayed raw material quickly solidify, spraying one layer to solidify one layer, The layers are stacked to form a reflective polarizing film in which the first refractive index film and the second refractive index film are alternately laminated and has more than hundreds of layers of films.

In an embodiment of the present invention, the thickness of one of the first refractive index film and the second refractive index film changes gradually along the stacking direction.

In an embodiment of the present invention, the first material and the second material are two kinds of polymers with different refractive indices.

The present invention also provides a reflective polarizing film preparation device based on 3D printing, including a control system and a mechanical system. The mechanical system completes the printing; the mechanical system includes a power unit and a printing unit, the power unit drives and regulates the working position of the printing unit, and the printing unit includes a feeding chamber and a printing head.

In one embodiment of the present invention, the print head is a dot print head, a line print head, or an arrayed area print head, and the line print head and the array type area print head are all combined by a single print head made.

In one embodiment of the present invention, the print head is a single print head, and the single print head includes a pipeline for feeding materials and a nozzle connected to the discharge end of the pipeline, and the outer sides of the nozzles are respectively A piece of convergent sheet for controlling the size of the nozzle is hinged, and the convergent sheet is respectively connected to the frame of the printer via its own actuator.

In one embodiment of the present invention, the print head is a single print head, and the single print head includes a pipeline for feeding materials and a nozzle connected to the discharge end of the pipeline. There is a telescopic material to control the size of the spout, and an actuator connected to the printer frame and used to control the direction of the spout is provided on the outside of the spout.

In an embodiment of the present invention, the actuator is an electrostrictive material actuator, and the electrostrictive material actuator includes electrodes for generating an electric field to drive the electrostrictive material, the electrostrictive material, The substrate, the electrode support and the transmission rod, the electrostrictive material adopts the series form in the mechanical structure, and adopts the parallel form in the circuit structure.

In an embodiment of the present invention, the actuator is a magnetostrictive material actuator, and the magnetostrictive material actuator includes a magnetostrictive material and a housing for generating a magnetic field to drive the magnetostrictive material coil and transmission rod.

In an embodiment of the present invention, the pipeline includes a heating section, a feeding section, and a nozzle, and a heating element for heating the material is arranged on the periphery of the heating section.

The beneficial effect of the present invention is to overcome the complex preparation process and low production efficiency existing in the existing reflective polarizing film preparation method, and propose a 3D printing-based reflective polarizing film preparation method and device, which can precisely control the reflectivity The shape, arrangement and thickness of the polarizing film can improve the surface cleanliness and precision of the reflective polarizing film, simplify the preparation process, and improve the production efficiency. It has strong practicability and broad application prospects.

Description of drawings

Fig. 1 is a schematic diagram of a conventional prism film structure.

Fig. 2 is a schematic diagram of a conventional brightness enhancing film manufacturing device.

Fig. 3 is a schematic structural diagram of a conventional reflective polarizing film.

Fig. 4 is a schematic structural diagram of a device according to an embodiment of the present invention.

FIG. 5 and FIG. 6 are a schematic view of the internal structure and a schematic cross-sectional view of a structure of a single print head according to an embodiment of the present invention.

Fig. 7 and Fig. 8 are schematic structural diagrams and schematic cross-sectional diagrams of the electrostrictive material actuator.

Fig. 9 is a schematic structural view and a schematic cross-sectional view of a magnetostrictive material actuator.

10 and 11 are schematic diagrams of the internal structure and cross-sectional diagrams of another structure of a single print head according to an embodiment of the present invention.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

The preparation method of reflective polarizing film based on 3D printing of the present invention comprises the following steps:

Step S1, establish a three-dimensional digital model of the reflective polarizing film, and convert it into a work instruction for controlling the work of the 3D printing device, including the first instruction for printing the first refractive index film of the reflective polarizing film and the second instruction for printing the reflective polarizing film. Second instruction for refractive index films.

Step S2, put the first raw material for printing the first refractive index film and the second raw material for printing the second refractive index film into the feeding chamber of the 3D printing device respectively, and convert the first raw material and the second raw material into a liquid state. The first raw material and the second raw material are two high molecular polymers with different refractive indices.

Step S3, the 3D printing device alternately executes the first instruction and the second instruction, and the printing head alternately sprays the liquid first raw material and the second raw material into the forming area, and makes the sprayed raw material quickly solidify, spraying one layer to solidify one layer, The layers are stacked to form a reflective polarizing film in which the first refractive index film and the second refractive index film are alternately laminated and has more than hundreds of layers of films. The thickness of one of the first refractive index film and the second refractive index film gradually changes along the stacking direction.

The present invention also provides a 3D printing-based reflective polarizing film preparation device matched with the above method, including a control system and a mechanical system. The control system establishes a three-dimensional digital model of the reflective polarizing film and converts it into a mechanical system The working instructions are used to control the mechanical system to complete the printing; the mechanical system includes a power unit and a printing unit, the power unit drives and regulates the working position of the printing unit, and the printing unit includes a feeding chamber and a printing head.

Referring to FIG. 4 , it is a schematic structural diagram of a reflective polarizing film preparation device according to an embodiment of the present invention. The device includes a control system and a mechanical system. The control system provides instructions for the mechanical system, establishes a three-dimensional digital model of the reflective polarizing film through computer modeling, and then uses a computer program to convert the three-dimensional digital model into work instructions for the mechanical system, and controls the mechanical system through the instructions to complete the printing of the model . The mechanical system includes a power unit (not shown) and a printing unit. The power unit (not shown) is connected with the cross slide 22b to realize the driving and regulation of the working position of the printing unit 21b. The printing unit includes a feeding chamber 21b and a printing head 27b.

The specific preparation steps of the reflective brightness-enhancing film in this embodiment are: a. Establish a three-dimensional digital model of the reflective polarizing film in the computer modeling system, and use a computer program to convert it into a work order for the mechanical system, including printing the reflective film. A first instruction for a first refractive index film 24b of a polarizing film and a second instruction for printing a second refractive index film 23b of a reflective polarizing film. b. Put the first raw material for printing the first refractive index film and the second raw material for printing the second refractive index film into the feeding chamber of the 3D printing device, and use melting technology to convert the first raw material and the second raw material into a liquid state ;

Step S3, the mechanical system alternately executes the first instruction and the second instruction, correspondingly alternates between two materials with different refractive indices, and the print head alternately sprays the liquid first and second materials into the forming area, the materials are rapidly cooled and solidified, and sprayed One layer is solidified one by one, so from left to right, alternately, and the layers are stacked to form a reflective polarizing film with more than hundreds of layers of thin films alternately stacked with the first refractive index film and the second refractive index film.

In the present invention, the print head may be a single print head, or a linear, planar or array print head. In the above embodiments, the printing head is a linear printing head. In another embodiment described below, the printhead is a single printhead.

The 3D printing device of this embodiment includes a material feeding pipeline 8 . The material is the material that needs to be printed, which can be but not limited to thermoplastics, alloys, metal powders, light-hardening resins and other materials. The pipeline includes a heating section, a feeding section, and an outlet. Heating elements 7 are arranged on the periphery of the heating section. The fed materials are heated in the heating section and pushed into the feeding section by subsequent materials. The materials are sent from the feeding section to the outlet, and finally printed on the working platform from the outlet. Curing and shaping.

When the material is conveyed to the outlet and printed on the working platform, its size is determined by the size of the outlet, and its direction is determined by the deflection direction of the outlet, that is, the outlet of the printing equipment has a decisive effect on the final size and printing direction of the printed material.

The 3D printing equipment of this embodiment is provided with an adjustment device at the exit, and there are two groups of adjustment devices, each group of adjustment devices includes two actuators 4, and the adjustment devices of the same group are arranged symmetrically. Two sets of adjustment devices are respectively placed on the upper, lower and left sides of the outlet. The fixed end of the actuator is rigidly connected to the support body 5 of the printing equipment, and the free end of the actuator is hinged to the convergent plates 1 and 2. Due to the deformation of the retractor under the action of the electric field or magnetic field, the retractor will push the convergence plate to move to realize the adjustment of the caliber and direction.

The actuator 4 used in the 3D printing device of this embodiment may be an electrostrictive material actuator. This actuator comprises an electrode 41 for generating an electric field to drive the electrostrictive material, an electrostrictive material 42 , a substrate 43 , an electrode support 44 and a drive rod 45 . Because the strain of a single piece of electrostrictive material 42 is limited, the electrostrictive material 42 adopts a series connection in mechanical structure and a parallel connection in circuit structure.

The actuator 4 used in the 3D printing device of this embodiment may be a magnetostrictive material actuator. This actuator comprises a magnetostrictive material 46, a housing 47, a coil 48 for generating a magnetic field that drives the magnetostrictive material and a transmission rod 49.

The actuators 4 used in the 3D printing device of this embodiment are powered independently. Each set of actuators controls magnitude and direction adjustment in one direction.

As shown in FIG. 6 , the convergent sheets 1 and 2 at the outlet respectively control the size of the two directions of the outlet and the printing direction. The convergent pieces are connected by flexible material 3 . What Fig. 5 shows is the situation of 4 astringent pieces, the present invention is not limited to use 4 astringent pieces, can increase according to need. When the same voltage is applied to the oppositely arranged actuators 4, once the expansion and contraction amount is reached, the converging pieces 12 will act synchronously, and the size of the outlet will change. When different voltages are applied to the oppositely arranged actuators 4, the amount of expansion and contraction is inconsistent, the actions of the convergent plates 1 and 2 are different, the direction of the center of the outlet changes, and the size of the nozzle changes at the same time.

In the electrostrictive material actuator shown in FIG. 7 , a plurality of pieces of electrostrictive material 42 are used, and they are connected in series in the stretching direction to enlarge the strain effect. At the same time all electrostrictive materials 42 are in the same electric field. The amount of deformation of the electrostrictive material is determined by the electric field strength.

As shown in FIG. 8 , which is a cross-sectional view of the electrostrictive material actuator, the electrode support 44 is made of insulating material to support the electrodes.

Using PMN-based relaxor ferroelectric (1-y)[(1-x)PMN-xPT]-yWO3, when x=0.1～0.13 and y=0.01～0.015, its electrostriction coefficient is as high as . Taking the structure of the electrostrictive material actuator shown in Figure 7 as an example, assuming that the length of 8 pieces of electrostrictive material 42 connected in series is 16mm, and the height of a single piece of electrostrictive material 42 is 1mm, then a voltage of 190V is applied to the electrodes At this time, the expansion and contraction amount of the single-side actuator is 0.5, and the simultaneous expansion and contraction of both sides can reduce the outlet by 1. When the voltage is removed, the size of the nozzle will return to the original state. When the voltage applied to the pole plate changes within the range of 0-1000V, the contraction range of the nozzle of this structure is 0-27.52.

When the above materials and structures are used and voltage is applied to only one side of the electrostrictive actuator, the center of the nozzle is shifted to one side. When 190V voltage is applied to one side and no voltage is applied to the other side, the center of the nozzle is shifted by 0.5.

As shown in FIG. 9 , in the magnetostrictive material actuator, the coil 48 generates a magnetic field to drive the magnetostrictive material 46 after being energized, and its deformation is related to the magnetic induction intensity.

Using magnetostrictive material, its magnetostriction coefficient is as high as . Assume that the coil in the magnetostrictive material actuator has 1000 turns, the diameter of the magnetostrictive material actuator is 2 mm, and the length of the magnetostrictive material is 10 mm. When the coil is supplied with 220V and 50V voltage, the elongation of the single-side magnetostrictive material actuator is 1.7, and the expansion and contraction of both sides can make the outlet shrink by 3.4. When the frequency of the applied voltage is maintained at 50HZ, and the magnitude changes within the range of 0-500V, the contraction range of the spout of this structure is 0-18.

The 3D printing device of this embodiment can also be implemented using a blocking structure, which is characterized in that the stretchable material 10 is placed inside the outlet, and the electrode 9 or coil is placed on the corresponding position of the shell 13 of the 3D printing device. The stretchable material 10 placed inside the outlet is deformed under the action of electric field or magnetic field, and this deformation can block part of the space of the outlet to realize the adjustment of the size of the outlet. The adjustment of the outlet direction is still implemented by means of an actuator, the difference is that the deflection occurs in the feed section 15 of the material pipeline when the blocking structure is used.

As shown in FIG. 10 , it is a cross-sectional view of the blocking structure. In the figure, electrostrictive material is used, so electrodes 9 are arranged. If magnetostrictive material is used, a coil should be wound on the casing 13 . The stretchable material 10 is deformed under the action of the electric field generated by the electrode 9, so that the size of the outlet changes.

As shown in FIG. 11 , the heater 14 in the blocking structure heats the incoming materials, and the materials are finally printed on the working platform from the outlet. The electrodes 9 fixed on the casing 13 generate an electric field to deform the electrostrictive material 10 and change the size of the outlet. The retractor 11 deflects the outlet to change the printing direction.

The stretchable material 10 uses the electrostrictive material PMN-based relaxor ferroelectric (1-y)[(1-x)PMN-xPT]-yWO3, when x=0.1～0.13 and y=0.01～0.015, print The diameter of the nozzle shell is 10 mm, and the thickness of the telescopic material 10 is 1 mm. When the plate voltage changes in the range of 0-1000V, the range of the nozzle size is 0-0.0172.

The stretchable material 10 is made of a magnetostrictive material, the diameter of the printing head shell is 10 mm, the thickness of the stretchable material 10 is 1 mm, and the coil has 100 turns. When the range of the added voltage is 0V, 50HZ - 1000V, 50HZ, the range of the nozzle size is 0 - 115.44.

The stretcher 11 uses the electrostrictive material PMN-based relaxor ferroelectric (1-y)[(1-x)PMN-xPT]-yWO3, when x=0.1～0.13 and y=0.01～0.015, with The structure of the electrostrictive material actuator shown in FIG. 7 is taken as an example, assuming that the length of two pieces of electrostrictive material 42 connected in series is 3 mm, and the height of a single piece of electrostrictive material 42 is 1 mm. When a voltage of 500V is applied to the electrostrictive actuator on one side, the center of the nozzle deflects 0.645 to one side.

The stretcher 11 uses magnetostrictive material, the diameter of the magnetostrictive material actuator is 2mm, the length of the magnetostrictive material is 2mm, and the coil has 500 turns. When a voltage of 220V, 50HZ is applied to the single-side magnetostrictive material actuator, the center of the nozzle is shifted to one side by 5.6.

The above are the preferred embodiments of the present invention, and all changes made according to the technical solution of the present invention, when the functional effect produced does not exceed the scope of the technical solution of the present invention, all belong to the protection scope of the present invention.

Claims (10)

1. A method for preparing reflective polarizing film based on 3D printing, characterized in that, comprising the following steps: Step S1, establish a three-dimensional digital model of the reflective polarizing film, and convert it into a work instruction for controlling the work of the 3D printing device, including the first instruction for printing the first refractive index film of the reflective polarizing film and the second instruction for printing the reflective polarizing film. Second Directive for Refractive Index Films; Step S2, putting the first raw material for printing the first refractive index film and the second raw material for printing the second refractive index film into the feeding chamber of the 3D printing device respectively, and converting the first raw material and the second raw material into a liquid state; Step S3, the 3D printing device alternately executes the first instruction and the second instruction, and the printing head alternately sprays the liquid first raw material and the second raw material into the forming area, and makes the sprayed raw material quickly solidify, spraying one layer to solidify one layer, The layers are stacked to form a reflective polarizing film in which the first refractive index film and the second refractive index film are alternately laminated and has more than hundreds of layers of films. 2. A method for preparing a reflective polarizing film based on 3D printing according to claim 1, wherein the thickness of one of the first refractive index film and the second refractive index film gradually changes along the stacking direction. 3. A method for preparing a reflective polarizing film based on 3D printing according to claim 1, wherein the first raw material and the second raw material are two kinds of high molecular polymers with different refractive indices. 4. A reflective polarizing film preparation device based on 3D printing, characterized in that it includes a control system and a mechanical system, and the control system sets up a three-dimensional digital model of the reflective polarizing film, and converts it into a work order of the mechanical system, to Control the mechanical system to complete the printing; the mechanical system includes a power unit and a printing unit, the power unit drives and regulates the working position of the printing unit, and the printing unit includes a feeding chamber and a printing head. 5. a kind of reflective polarizing film preparation device based on 3D printing according to claim 4, is characterized in that, described printing head is dot printing head, linear printing head, or arrayed planar printing head, so The above-mentioned linear print head and array type area print head are all combined by a single print head. 6. A kind of reflective polarizing film preparation device based on 3D printing according to claim 4, it is characterized in that, described printing head is a single printing head, and described single printing head comprises the pipeline for feeding material and Connected to the nozzle on the discharge end of the pipeline, a piece of convergent piece used to control the size of the nozzle is respectively hinged on the outside around the nozzle, and the convergent pieces are respectively connected to the frame of the printer through their respective actuators. 7. A kind of reflective polarizing film preparation device based on 3D printing according to claim 4, is characterized in that, described printing head is a single printing head, and described single printing head comprises the pipeline for feeding material and Connected to the nozzle on the discharge end of the pipeline, the inner side of the nozzle is provided with stretchable materials to control the size of the nozzle, and the outer side of the nozzle is provided with an actuator connected to the printer frame and used to control the direction of the nozzle. 8. A device for preparing a reflective polarizing film based on 3D printing according to claim 6 or 7, wherein the actuator is an electrostrictive material actuator, and the electrostrictive material actuates The device includes electrodes for generating an electric field to drive the electrostrictive material, the electrostrictive material, the substrate, the electrode support and the transmission rod, and the electrostrictive material adopts a series form in a mechanical structure, and uses a parallel form in a circuit structure . 9. The device for preparing a reflective polarizing film based on 3D printing according to claim 6 or 7, wherein the actuator is a magnetostrictive material actuator, and the magnetostrictive material actuates The device consists of a magnetostrictive material, a housing, a coil for generating a magnetic field that drives the magnetostrictive material, and a drive rod. 10. A kind of reflective polarizing film preparation device based on 3D printing according to claim 6 or 7, characterized in that, the pipeline includes a heating section, a feeding section, and a nozzle, and is arranged on the periphery of the heating section to Heating elements for heating the material.